import logging
import os
import sys


def setup_logging(log_dir, config_name):
    """Configures logging to output to both file and console.

    Args:
        log_dir (str): The directory where the log file should be saved.
        config_name (str): The name of the configuration run, used for the log filename.
    """
    # Ensure log directory exists
    os.makedirs(log_dir, exist_ok=True)

    log_filename = f"{config_name}_train.log"
    log_filepath = os.path.join(log_dir, log_filename)

    # Configure the root logger
    logging.basicConfig(
        level=logging.INFO,  # Log INFO level and above (INFO, WARNING, ERROR, CRITICAL)
        format="%(asctime)s [%(levelname)s] %(message)s",
        datefmt="%Y-%m-%d %H:%M:%S",
        handlers=[
            logging.FileHandler(log_filepath),  # Log to a file
            logging.StreamHandler(sys.stdout),  # Log to the console (stdout)
        ],
        # Force=True ensures that if basicConfig was called before (e.g., by a library),
        # this configuration will overwrite it. Use with caution if libraries might
        # configure logging themselves in complex ways.
        force=True,
    )

    logging.info(f"Logging configured. Log file: {log_filepath}")


# Example usage (can be removed or kept for testing):
if __name__ == "__main__":
    print("Testing logging setup...")
    setup_logging("temp_logs", "test_config")
    logging.info("This is an info message.")
    logging.warning("This is a warning message.")
    logging.error("This is an error message.")
    print("Check 'temp_logs/test_config_train.log' and console output.")